The present invention relates to air belt apparatuses which protect occupants in a movable body such as a vehicle, etc., when the movable body collides, etc., and to air belts comprised therein. More specifically, the present invention relates to an air belt apparatus and to an air belt, in which a bag is expanded by a gas supplied by a gas generator.
An air belt apparatus of this type is disclosed in Japanese Unexamined Patent Application Publication No. 5-85301. FIG. 5 is a perspective view of the disclosed air belt apparatus.
This air belt apparatus 1 includes an air belt 2 which extends in an inclined manner from the right side to the left side of an occupant, a webbing 2a which is connected to the air belt 2 at an end thereof, a wrap belt 3 which extends from the right side to the left side of the occupant, a buckle 4 which is disposed on the floor portion, etc., of a vehicle body, a tongue 5 which is inserted into and engaged with the buckle 4 when the belt is fastened, and an anchor 6 which guides the webbing 2a. 
The webbing 2a is constructed of normal belt material which is similar to the material used for typical, conventional seat belts, and is slidably inserted through the anchor 6. The other end of the webbing 2a is connected, in such a manner that the webbing 2a can be wound, to a seat belt retractor (ELR) 7 which is fixed to the vehicle body, and which is provided with an emergency locking mechanism.
The upper end of the air belt 2 is connected to the webbing 2a by sewing, etc., and the lower end thereof is connected to the tongue 5.
The wrap belt 3 is constructed of normal belt material which is similar to the material used for typical, conventional seat belts. One end of the wrap belt 3 is connected to a tongue 5, and the other end is connected to a seat belt retractor (ELR) 8, which is fixed to the vehicle body. The buckle 4 is connected to a gas generator 9 which generates a high-pressure gas when it is activated in an emergency situation, for example, when the vehicle is in a collision.
Both the tongue 5 and the buckle 4 include a passage through which the gas generated by the gas generator 9 passes to the air belt 2.
The air belt 2 is constructed of a wide, band-like shaped bag which is folded to make it thinner and which is enclosed by a cover. The thin, band-like shape of the air belt 2 is maintained in normal situations. The air belt apparatus 1 is used in a similar manner to a normal seat belt apparatus. When the vehicle collides, etc., and the gas generator 9 is activated, the air belt 2 inflates to the position indicated by a double-dotted chain line in FIG. 5 in order to protect the occupant.
In the above-described conventional air belt apparatus 1, the webbing 2a, which is connected to the air belt 2, is wound by the retractor 7. This arrangement is required because the air belt 2 cannot easily pass through the anchor 6 and the retractor 7 cannot easily wind the air belt 2 due to the relative thickness of the air belt 2 compared to the webbing 2a. 
Accordingly, it is an object of the present invention to provide an air belt apparatus in which the webbing 2a is omitted, and in which a belt, which is integrally formed with an expanding portion of an air belt, can directly be inserted through an anchor and wound by a retractor.
According to the present invention an air belt is provided. The air belt includes a belt, one half thereof in the lateral direction being formed as a hollow expandable portion which is able to expand, and the other half thereof in the lateral direction being formed as a non-expanding portion. The air belt further includes a bag which is contained in the expandable portion of said belt. The bag is configured to receive gas, which is injected so as to expand the air belt. In addition, the belt is constructed by continuously and integrally forming the expandable portion and the non-expanding portion with a woven or knit fabric, and wefts are inserted through the non-expanding portion.
The non-expanding portion of the air belt is solid. As a result, the non-expanding portion smoothly slides through an anchor, is smoothly wound by a retractor, and is smoothly extracted. In addition, since the wefts are inserted through the non-expanding portion, the non-expanding portion does not expand in the lateral direction when it is wound by the retractor. Accordingly, the non-expanding portion is wound by the retractor in a smooth manner.
In an air belt apparatus according to the present invention, the expansion of the air belt is realized by a gas generator. The air belt apparatus may further include a tongue to which an end of the air belt is connected and a retractor which winds the air belt from the other end thereof, and is installed inside a vehicle, etc.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.